Lamp holder for circular tubular lamps



Dec. 19, 11950 J. M. PISTEY ETAL 2,534,956

LAMP HOLDER FOR CIRCULAR TUBULAR LAMPS Filed April 15, 1946 -In\/enbo1r-s= John M. Pistqg, Frank C. DeReamer-,

Their- Abbot-n e Patented Dec. 19, 1950 LAMPHOLDER'FOR CIRCULAR TUBULAR LAM John M. iistey, Fairfield, 001111., and Erank iC.

doe Reamer, "Lake Worth, Fla.,.assignors;to General Electric Company, a corporation ,of New York Application April 15, 1946, Serial No. 662,128

9 Claims.

Our inventionrelates to lamp holders and more particularly to lamp holders for circular tubula r discharge lamps, for example, circular fluorescent lamps of the type now coming on the market.

Circular fluorescent lamps are generally provided with a. contact base at one place in the periphery of the lamp tube. The contact base is usually formed as a tube and has radially extending contact pins whereby electrical connectlons are made to the lamp electrodes. Such lamps :are preferably supported at two points at least. Since electrical connection must be made to. the, lamp .base, the latter naturally indicates one point for the lamp support; the other point i orpoints of' support may be spaced around the loop of thelamp. I

The structure of the connecting support must be such that adequate electrical contact with the lamp pins is made at all times and even though the lengths of the pins may vary due to manufacturing tolerances. Mechanically, the support structure must securely hold the lamp, even under vibration conditions, while at the same time providing for easy replacement. Moreover, in order to provide adaptability to a widevariety of uses, the elements of a complete lam-pholder should be decorative as well as utilitarian and should interfere as little as possible with the light produced by the circular lamp. 3

Accordingly, a primary object of our invention is the provision of an improved construction ofa lamp holder fixture for circular lamps which shall satisfy the foregoing requirements and which includesv elements adapted for use in var ious fixturearrangements and particularly adapted :for use with fixture arms such as form parts of floor lamps, table lamps, or the like. A further object of our invention is the provision of an improved lampholder or contact receptacle element for aiding in the support of a circular fluorescent lamp and for making contact with the lamp base. A still further object of our invention is the provision of improved support elements for acircular fluorescent lamp.

In carrying out. our invention we provide a lampholder fixture having a plurality of arms extending outwardly from a base and terminating ina circle. Lamp supporting and contacting elements are mounted at the ends of these arms and aresimilarly shaped and designed to engage small portions only of the lamp tube. The lampholder proper, or contact receptacle, or socket element, as it is variouslycalled, is constructed so that it may be mounted on a fixture (Cl. Mew-5.1.12) l 2. arm or the like and is provided with contact members having freely floating, spring =biass'ed contact elements therein. "The lamp supporting elements which are not required to provide tor electrical connection, generally described :as supports or tension supports, are also construoted for mounting on a fixture :arm or the like; these supports include a spring :tensioned, pivotally mounted clamp element which is adapted toengage the lam-ptube.

In the accompanying drawing, Fig. 1 is a plan view of a circular fluorescent lampmounted on a lamp holder constructed in accordance'w-i thour invention; Fig. 2 is .a view of the holder in elevation; Fig. 3 is a partial sectional 'Vl'GW of the holder taken along the line :3'-13 of :Fig. 1; .Fig. 4 is a view of another part of our holder taken along the line 4-4 of Fig. l, and Fig. 5 is anonlarged view in section of the receptacle contact structure.

Referring to the drawing, our lamp holder is provided with spaced supports fl for engaging the Wall of a circular fluorescent lamp and .a contact receptacle 2 supporting .and making. anelectrical connection with the base-of the lamp supports I .and receptacle '2. are each mounted on a tubular .fixture arm 3 forming part of a table lamp 4. In the particular form of table lamp illustrated, three fixture arms areemployed but it should be manifest that, the number of awe may be increased or decreased at will depending uponthe type .of lamp with which our holder is used. We have illustrated only one form of the many forms of table or floor lamps with which our invention may be used. it should be noted, however, that. the circular. fluorescent. lamp; is preferablysupported on at leastytwo points which means that a contact receptacle ,2. .is. used to support the base and one other support I to en.- gage and support the loop-of the lamp.

Turning now to the construction of the con.- tact receptacle 2 and referring to Fig. 3, the .receptacle includes a base 5 formed of. any suit.- able .insulating'material such as a molded plasttic. Base 5 is formed with a curved surface 5 which fits around and. closely engages the contact base .1 of. the.- circular fiuorescentlamp- It should be noted that the. lamp base is formed as a tube to provide a continuation of the lamp tube and that the lamp contact pins extend 'radially from the base. A portion of the curved surface of the receptacle is provided with a raised projection 8 which fits into a recess 9 in the lampbase and assists in centering the base on the receptacle. In order to make an electrical connection with the lamp, the receptacle is pro vided with four cylindrical contact members l0, only two of which are shown. These receive the four lamp contact pins H which are electrically connected to the filaments at each end of the lamp tube.

As shown in Fig. 5, the cylindrical contact members I are molded into the base 5. Each contact member has a flared end for guiding and receiving the lamp prong which extends into the contact through an opening l2 in the raised projection 8. Each contact member carries a ball contact I3, preferably made of brass, which is biased by means of a spring l4 into engagement with the lamp contact pin. Outward movement of the ball contact is limited by one or more projections l5 struck inwardly from the wall of the contact cylinder. The ball floats freely in the contact cylinder. It compensates for any manufacturing tolerances in the length of the lamp contact pin. Moreover, there is a tendency for the ball to rotate slightly whenever the lamp is mounted on or removed from the holder. This means that a new contact surface is presented to the lamp contact pin each time the lamp is replaced so that a good electrical connection is maintained between the lamp and the holder. An electrical conductor I6 is fastened in any suitable way, as by soldering, to each contact cylinder to provide means for wiring the holder to a fluorescent lamp ballast and starting switch in a manner well understood in the art.

In order to mount the base 5 on the fixture arm 3, the base is formed with an integral extension I'! which fits into a collar l8 to which it is fastened in any suitable manner as by a set screw is. The collar I8, in turn, is mounted on the fixture arm 3 and is fastened in position by a set screw 20.

Turning now to the construction of the tension support elements and referring to Fig. l, the support I comprises a collar 2| formed as a casting and which is provided with a recess 22 for receiving the fixture arm 3. It is fastened to the arm in any suitable manner, for example, by means of a set screw 23. A clamp 24 of insulating material is pivotally mounted on collar 2| by a pin 25 and is provided with a curved surface 26 for engaging the periphery of the lamp tube. formed on the upper surface of collar 21. When the parts are in assembled position, the guide ridge extends into a recess 28 formed in the clamp 24. In this way, the ridge 2? serves as a guide to insure straightline pivotal movement of the clamp about pin 25. Clamp 24 is biased into engagement with the lamp tube by means of a compression spring 29 seated in recess 28. One end of the spring engages a projection 30 formed in ridge 2? while the other end surrounds projection 3| on clamp 24. The projections serve to hold the spring in position in the recess. In this location, the spring is hidden by the side walls of the recess 28, as will appear from Fig. 2. Although the spring tends to rotate the clamp 24 clockwise, in the showing of Fig. 4, rotation of the clamp is limited by bosses 32 which engage the top surface of collar 2|.

One contact receptacle 2 and at least one tension support l are mounted on a lamp fixture to form the complete holder. In the form of the invention illustrated, two of the supports l are used and each is mounted on a fixture arm 3 of the lamp along with the contact receptacle 2. To mount a circular lamp, the lamp base is Pin 25 extends through a guide ridge 21 I first mounted on the contact receptacle 2 with the lamp pins seated in the cylindrical contact members l0. Then the clamps 24 are pivoted to permit the lamp tube to snap over into position on the curved surfaces 25. Springs 29 force the clamps 24 firmly into engagement with the lamp tube. In addition, the springs tend to pull the lamp base firmly into engagement with the contact receptacle.

It will be apparent that in mounting the lamp, it must be rotated or moved in a slight are about the base as a center. This means that the lamp contact pins must pivot or move sidewise slightly within the cylindrical contact members 10. The members are made of a sufiilcient diameter to permit this without damage to the lamp. In other words, the lamp pins do not necessarily make electrical contact with the side walls of the cylindrical contact members l0 but rather are engaged by the floating contact balls l3. The curved surface 6 of the receptacle cooperates with the curved surface of the lamp base i to permit relative movement between these two parts as the lamp contact pins pivot in mounting the lamp.

What we claim as new and desire to secure by Letters Patent of the United States, is:

1. A lampholder fixture for a circular tubular lamp comprising, in combination, a base, a plurality of arms extending outwardly from said base and terminating in a circle concentric with the lamp and in a plane parallel to the lamp plane, lamp supporting elements mounted on the end of each of said arms, all of said elements being provided with a similar curved contour having a concave surface shaped to engage a portion of the cross-sectional periphery of the lamp, a lamp contact pin receiving receptacle mounted in the concave surface of one of said elements, and each of the other of said elements comprising a tension support including a recessed clamp member pivotally mounted on the end of its respective arm and spring means in said recess for biasing said clamp member into engagement with the lamp tube.

2. A lampholder for a circular tubular lamp having a tubular base with contact pins extending radially from the base, said lampholder comprising an insulating member having a curved contour with a concave surface, a portion of which is shaped to engage the cross-sectional periphery of the lamp base, a plurality of lamp contact pin receiving cylindrical contact members recessed in said concave surface of said insulating member, contact elements freely floating in said contact members and spring means biassing said contact elements toward said surface.

3. A lampholder for a circular tubular lamp having a tubular base with contact pins extending radially from the base, said lampholder comprising an insulating member having a curved contour with a concave surface, a portion of which is shaped to engage the cross-sectional periphery of the lamp base, a plurality of lamp contact pin receiving cylindrical contact members recessed in said concave surface of said' insulating member, ball contacts freely floating in said contact members, spring means biassing said ball contacts toward said concave surface, and means for mounting said insulating member on a support.

4. A lampholder for a circular tubular lamp having a tubular base with contact pins extending radially from the base, said lampholder comprising an insulating member having a curved contour with a concave surface, a portion of which is shaped to engage the crosssectional periphery of the lamp base, a plurality of lamp contact pin receiving cylindrical contact members recessed in said concave surface of said insulating member, ball contacts freely floating in said contact members, spring means biassing said ball contacts toward said surface and a recessed base for said insulating member for mounting the same on lamp fixture arm.

5. A tension support for a circular tubular lamp comprising a clamp member having a curved contour with a concave surface a portion of which is shaped to engage the cross-sectional periphery of the la: tube, r inber having a recess, supporting member ac-,pted to be mounted on a fixtui arin, means pivotally mounting clamp member on supporting member and spring means in said recess for biassing said clamp member away from said supporting member about said pivotal mounting in the direction of said concave surface.

6. A tension support for a circular tubular lamp comprising a clamp member having a curved. contour with a concave surface a portion of which is shaped to engage the crosssectional peripher of the lamp tube, said member having a recess, a supporting member adapted to be mounted on a lamp fixture arm and having an abutment thereon adapted to fit into said recess, a pivot pin passing through a wall of said recess and into said abutment for pivotally mounting said clamp member on said supporting member, and spring means in said recess for biassing said clamp member away from said supporting member about said pivot in the direction of said concave surface.

7. A tension support for a circular tubular lamp comprising a clamp member having a curved contour with a concave surface, a portion of which is shaped to engage the crosssectional periphery of the lamp tube, a supporting member adapted to be mounted on a lamp fixture arm and having a. guide member thereon, means pivotally mounting said clamp member on said supporting member, said clamp member having a recess the walls of which are adapted to cooperate with said guide member to restrict movement of the clamp to pivotal movement, and spring means in said recess for biassing said clamp member away from said supporting member about said pivotal mounting in the direction of said concave surface.

8. A tension support for a circular tubular lamp comprising a, clamp member having a curved contour with a concave surface, a portion of which is shaped to engage the cross sectional periphery of the lamp tube, a supporting member adapted to be mounted on a lamp fixture arm and having a guide member thereon, means pivotally mounting said clamp member on said supporting member, said clamp member having a recess the walls of which are adapted to cooperate with said guide member to restrict movement of the clamp to pivotal movement, and a coiled spring in said recess extending between said supporting member and said clamp member for biassing the clamp about said pivotal mountin in the direction of said concave surface.

9. A tension support for a circular tubular lamp comprising a. clamp member having a curved contour with a concave surface, a portion of which is shaped to engage the crosssectional periphery of the lamp tube, an axially recessed supporting collar adapted to be mounted on a lamp fixture arm and having a guide member thereon, means pivotally mounting said clamp member on said supporting collar, said clamp member having a recess, the walls of which are adapted to cooperate with said guide member to restrict movement of the clamp to pivotal movement and a spring in said recess extending between said supporting collar and said clamp member for biassing the clamp about said pivotal mounting in the direction of said concave surface.

JOHN M. PISTEY. FRANK C. DE REAMER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

